An American citizen has been taken into custody in North Korea, according to the country's state media.

The man, referred to as Pae Jun-Ho, entered North Korea on November 3 as a tourist, and "committed a crime" against the country, the official Korean Central News Agency said.

"He was put into custody by a relevant institution," it added.

The US has no diplomatic ties with North Korea and KCNA said consular officials from the Swedish embassy, which acts on behalf of the US, had visited Mr Pae on Friday.

"Legal actions are being taken against Pae in line with the criminal procedure law (of North Korea)", the agency said without giving further details.

The arrest was first reported by a South Korean newspaper which had identified the detainee as a 44-year-old Korean-American tour operator.

KCNA said Mr Pae was detained as he entered the north-eastern port city of Rason, which lies inside a special economic zone near North Korea's border with Russia and China.

Several Americans have been held in North Korea in recent years.

Former US president Jimmy Carter won plaudits in 2010 when he negotiated the release of Aijalon Mahli Gomes, an American national who had been sentenced to eight years of hard labour for illegally entering from China.

On another mercy mission a year earlier in 2009, former president Bill Clinton won the release of US television journalists Laura Ling and Euna Lee, jailed after wandering across the North Korean border with China.